#include <iostream>
#include <algorithm>
#include <cstdio>
using namespace std;
int MAXX(int a, int b)
{
    return a > b ? a : b;
}
int main()
{
    int m, t, s, z;
    cin >> m >> t >> s;
    if (t == 0)
    {
        cout << 0 << endl;
        return 0;
    }
    /*
    z = m * t;
    z = z - s;
    z = z / t;
    */
    if (s % t == 0)
    {
        z = MAXX(0, m - s / t);
    }
    else
    {
        z = MAXX(0, m - s / t - 1);
    }
    cout << z << endl;
}